This invention relates to fish egg baits. It pertains particularly to a process of making from fish eggs, particularly from salmon eggs, improved bait eggs which more closely resemble natural fish eggs, with respect to their tactile and optical properties. In particular, the fish egg bait which is the product of the process of the present invention resembles natural fish eggs more closely than do the fish egg baits of the prior art with respect to plumpness, color, degree of translucency or transparency, and by being plastic or rubbery to the touch.
As is well known salmon eggs are a natural food for trout which coexist with the salmon in the spawning streams. For this reason salmon egg bait is a preferred bait for trout and has been available commercially for a long period of time.
To be suitable for this use, the fish egg bait of commerce must fulfill several requirements which are difficult of fulfillment.
Thus the eggs should be plump and have a normal shape and appearance. Their consistency should be uniform and plastic. Their color should be appropriate. They should be large enough to make it possible to impale them successfully on a hook. They should be tough enough so that when so impaled they will remain on the hook and withstand the stresses of casting. Their taste and texture should not be distasteful to a biting fish.
My U.S. Pat. No. 2,951,761 discloses a process for the preparation of fish egg bait which comprises a combination brine, heat and formaldehyde treating process for toughening and preserving fish eggs to make them suitable for use as bait. While the bait eggs produced by this process constitute a substantial article of commerce, the eggs tend to be hard, opaque, and whitish in color. In these important respects they accordingly are dissimilar to natural eggs.
In the foregoing and analagous prior art processes, an attempt is made to camouflage the eggs and overcome their unnatural color by dying the eggs with red, orange or fluorescent dyes. However this does not mask entirely the unnatural appearance of the bait.
In my copending patent application Ser. No. 601,133 filed Aug. 1, 1975 for UREA-TREATED FISH EGG BAIT, a process is disclosed for converting fish eggs to fish egg bait by first treating the eggs in a saline solution with heat and/or with formaldehyde, or other chemical hardening agents, for protein, until the eggs have become hard and opaque. Thereafter the hardened and opacified eggs are soaked in an aqueous urea solution. This introduces urea into the eggs and works a remarkable and beneficial conversion by which the eggs become plasticized and rubbery, instead of hard; translucent or transparent instead of opaque; and swollen to an extent such that they attain a size which makes them more suitable for use as fish bait.
It is the general purpose of the present invention to provide a urea-treating process for converting fish eggs to fish egg bait which process is much more rapid than is the process set forth in my above identified patent application, and which surprisingly leads to the production of a fish egg bait product which is of a greatly increased size, for example from 2 to 3 times the size of the eggs from which the product is derived.
These two advantages obviously are of the greatest commercial significance.
The increased speed of reaction decreases markedly the time required for manufacturing the bait product and cuts manufacturing costs correspondingly. Increasing the size of the eggs by two or threefold makes possible producing two or three times the amount of finished product from a given amount of fish egg feedstock, thereby increasing the market value of the fish egg bait product by a corresponding factor. It should be noted in this regard that the fish egg feed stocks for use in the presently described process are very expensive, costing several dollars a pound at the fish processing houses. Considering this, the economic advantage of hugely increasing the size of the eggs without degrading their other properties is immediately apparent.
Also apparent is the fact that the presently described process makes possible the utilization of eggs having such a small size that they otherwise could not be used as a feedstock. In other words, tiny eggs which are not of sufficient size to be impaled on a hook, or if so impaled fail to cover the hook satisfactorily, are swollen by the presently described process to a degree such that they become suitable for this purpose.
Further objects of the present invention are the provision of a bait fish eggs having the foregoing desirable attributes and which additionally are tough so that when impaled on a hook they will withstand casting; which have a taste not unpleasant to fish; and which may be preserved effectively so that when marketed they have a long shelf life.